next up previous
Next: IPC Hooks Up: Implementation Previous: Task Hooks

Program Loading Hooks

Many security modules, including Linux capabilities, DTE, SELinux, and SubDomain require the ability to perform changes in privilege when a new program is executed. Consequently, LSM provides a set of program-loading hooks that are called at critical points during the processing of an execve operation. The security field of the linux_binprm structure permits modules to maintain security information during program loading. One hook is provided to permit security modules to initialize this security information and to perform access control prior to loading the program, and a second hook is provided to permit modules to update the task security information after the new program has been successfully loaded. These hooks can also be used to control inheritance of state across program executions, for example, revalidating open file descriptors.

James Morris